Class: Net::IMAP::ResponseParser

# File 'lib/net/imap/response_parser.rb', line 1332

def accept_space
  if @token
    shift_token if @token.symbol == T_SPACE
  elsif @str[@pos] == " "
    @pos += 1
  end
end

# File 'lib/net/imap/response_parser.rb', line 1344

def accept_spaces
  shift_token if @token&.symbol == T_SPACE
  if @str.index(SPACES_REGEXP, @pos)
    @pos = $~.end(0)
  end
end

# File 'lib/net/imap/response_parser.rb', line 1178

def address
  match(T_LPAR)
  if @str.index(ADDRESS_REGEXP, @pos)
    # address does not include literal.
    @pos = $~.end(0)
    name = $1
    route = $2
    mailbox = $3
    host = $4
    for s in [name, route, mailbox, host]
      if s
        s.gsub!(/\\(["\\])/n, "\\1")
      end
    end
  else
    name = nstring
    match(T_SPACE)
    route = nstring
    match(T_SPACE)
    mailbox = nstring
    match(T_SPACE)
    host = nstring
    match(T_RPAR)
  end
  return Address.new(name, route, mailbox, host)
end

# File 'lib/net/imap/response_parser.rb', line 1148

def address_list
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    return nil
  else
    result = []
    match(T_LPAR)
    while true
      token = lookahead
      case token.symbol
      when T_RPAR
        shift_token
        break
      when T_SPACE
        shift_token
      end
      result.push(address)
    end
    return result
  end
end

# File 'lib/net/imap/response_parser.rb', line 1234

def astring
  token = lookahead
  if string_token?(token)
    return string
  else
    return astring_chars
  end
end

# File 'lib/net/imap/response_parser.rb', line 1287

def astring_chars
  combine_adjacent(*ASTRING_CHARS_TOKENS)
end

# File 'lib/net/imap/response_parser.rb', line 1279

def atom
  -combine_adjacent(*ATOM_TOKENS)
end

# File 'lib/net/imap/response_parser.rb', line 326

def body
  @lex_state = EXPR_DATA
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    result = nil
  else
    match(T_LPAR)
    token = lookahead
    if token.symbol == T_LPAR
      result = body_type_mpart
    else
      result = body_type_1part
    end
    match(T_RPAR)
  end
  @lex_state = EXPR_BEG
  return result
end

# File 'lib/net/imap/response_parser.rb', line 307

def body_data
  token = match(T_ATOM)
  name = token.value.upcase
  token = lookahead
  if token.symbol == T_SPACE
    shift_token
    return name, body
  end
  name.concat(section)
  token = lookahead
  if token.symbol == T_ATOM
    name.concat(token.value)
    shift_token
  end
  match(T_SPACE)
  data = nstring
  return name, data
end

# File 'lib/net/imap/response_parser.rb', line 513

def body_ext_1part
  token = lookahead
  if token.symbol == T_SPACE
    shift_token
  else
    return nil
  end
  md5 = nstring

  token = lookahead
  if token.symbol == T_SPACE
    shift_token
  else
    return md5
  end
  disposition = body_fld_dsp

  token = lookahead
  if token.symbol == T_SPACE
    shift_token
  else
    return md5, disposition
  end
  language = body_fld_lang

  token = lookahead
  if token.symbol == T_SPACE
    shift_token
  else
    return md5, disposition, language
  end

  extension = body_extensions
  return md5, disposition, language, extension
end

# File 'lib/net/imap/response_parser.rb', line 549

def body_ext_mpart
  token = lookahead
  if token.symbol == T_SPACE
    shift_token
  else
    return nil
  end
  param = body_fld_param

  token = lookahead
  if token.symbol == T_SPACE
    shift_token
  else
    return param
  end
  disposition = body_fld_dsp

  token = lookahead
  if token.symbol == T_SPACE
    shift_token
  else
    return param, disposition
  end
  language = body_fld_lang

  token = lookahead
  if token.symbol == T_SPACE
    shift_token
  else
    return param, disposition, language
  end

  extension = body_extensions
  return param, disposition, language, extension
end

# File 'lib/net/imap/response_parser.rb', line 639

def body_extension
  token = lookahead
  case token.symbol
  when T_LPAR
    shift_token
    result = body_extensions
    match(T_RPAR)
    return result
  when T_NUMBER
    return number
  else
    return nstring
  end
end

# File 'lib/net/imap/response_parser.rb', line 625

def body_extensions
  result = []
  while true
    token = lookahead
    case token.symbol
    when T_RPAR
      return result
    when T_SPACE
      shift_token
    end
    result.push(body_extension)
  end
end

# File 'lib/net/imap/response_parser.rb', line 475

def body_fields
  param = body_fld_param
  match(T_SPACE)
  content_id = nstring
  match(T_SPACE)
  desc = nstring
  match(T_SPACE)
  enc = case_insensitive_string
  match(T_SPACE)
  size = number
  return param, content_id, desc, enc, size
end

# File 'lib/net/imap/response_parser.rb', line 585

def body_fld_dsp
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    return nil
  end
  match(T_LPAR)
  dsp_type = case_insensitive_string
  match(T_SPACE)
  param = body_fld_param
  match(T_RPAR)
  return ContentDisposition.new(dsp_type, param)
end

# File 'lib/net/imap/response_parser.rb', line 599

def body_fld_lang
  token = lookahead
  if token.symbol == T_LPAR
    shift_token
    result = []
    while true
      token = lookahead
      case token.symbol
      when T_RPAR
        shift_token
        return result
      when T_SPACE
        shift_token
      end
      result.push(case_insensitive_string)
    end
  else
    lang = nstring
    if lang
      return lang.upcase
    else
      return lang
    end
  end
end

# File 'lib/net/imap/response_parser.rb', line 488

def body_fld_param
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    return nil
  end
  match(T_LPAR)
  param = {}
  while true
    token = lookahead
    case token.symbol
    when T_RPAR
      shift_token
      break
    when T_SPACE
      shift_token
    end
    name = case_insensitive_string
    match(T_SPACE)
    val = string
    param[name] = val
  end
  return param
end

# File 'lib/net/imap/response_parser.rb', line 346

def body_type_1part
  token = lookahead
  case token.value
  when /\A(?:TEXT)\z/ni
    return body_type_text
  when /\A(?:MESSAGE)\z/ni
    return body_type_msg
  when /\A(?:ATTACHMENT)\z/ni
    return body_type_attachment
  when /\A(?:MIXED)\z/ni
    return body_type_mixed
  else
    return body_type_basic
  end
end

# File 'lib/net/imap/response_parser.rb', line 432

def body_type_attachment
  mtype = case_insensitive_string
  match(T_SPACE)
  param = body_fld_param
  return BodyTypeAttachment.new(mtype, nil, param)
end

# File 'lib/net/imap/response_parser.rb', line 362

def body_type_basic
  mtype, msubtype = media_type
  token = lookahead
  if token.symbol == T_RPAR
    return BodyTypeBasic.new(mtype, msubtype)
  end
  match(T_SPACE)
  param, content_id, desc, enc, size = body_fields
  md5, disposition, language, extension = body_ext_1part
  return BodyTypeBasic.new(mtype, msubtype,
                           param, content_id,
                           desc, enc, size,
                           md5, disposition, language, extension)
end

# File 'lib/net/imap/response_parser.rb', line 439

def body_type_mixed
  mtype = "MULTIPART"
  msubtype = case_insensitive_string
  param, disposition, language, extension = body_ext_mpart
  return BodyTypeBasic.new(mtype, msubtype, param, nil, nil, nil, nil, nil, disposition, language, extension)
end

# File 'lib/net/imap/response_parser.rb', line 446

def body_type_mpart
  parts = []
  while true
    token = lookahead
    if token.symbol == T_SPACE
      shift_token
      break
    end
    parts.push(body)
  end
  mtype = "MULTIPART"
  msubtype = case_insensitive_string
  param, disposition, language, extension = body_ext_mpart
  return BodyTypeMultipart.new(mtype, msubtype, parts,
                               param, disposition, language,
                               extension)
end

# File 'lib/net/imap/response_parser.rb', line 391

def body_type_msg
  mtype, msubtype = media_type
  match(T_SPACE)
  param, content_id, desc, enc, size = body_fields

  token = lookahead
  if token.symbol == T_RPAR
    # If this is not message/rfc822, we shouldn't apply the RFC822
    # spec to it.  We should handle anything other than
    # message/rfc822 using multipart extension data [rfc3501] (i.e.
    # the data itself won't be returned, we would have to retrieve it
    # with BODYSTRUCTURE instead of with BODY

    # Also, sometimes a message/rfc822 is included as a large
    # attachment instead of having all of the other details
    # (e.g. attaching a .eml file to an email)
    if msubtype == "RFC822"
      return BodyTypeMessage.new(mtype, msubtype, param, content_id,
                                 desc, enc, size, nil, nil, nil, nil,
                                 nil, nil, nil)
    else
      return BodyTypeExtension.new(mtype, msubtype,
                                   param, content_id,
                                   desc, enc, size)
    end
  end

  match(T_SPACE)
  env = envelope
  match(T_SPACE)
  b = body
  match(T_SPACE)
  lines = number
  md5, disposition, language, extension = body_ext_1part
  return BodyTypeMessage.new(mtype, msubtype,
                             param, content_id,
                             desc, enc, size,
                             env, b, lines,
                             md5, disposition, language, extension)
end

# File 'lib/net/imap/response_parser.rb', line 377

def body_type_text
  mtype, msubtype = media_type
  match(T_SPACE)
  param, content_id, desc, enc, size = body_fields
  match(T_SPACE)
  lines = number
  md5, disposition, language, extension = body_ext_1part
  return BodyTypeText.new(mtype, msubtype,
                          param, content_id,
                          desc, enc, size,
                          lines,
                          md5, disposition, language, extension)
end

# File 'lib/net/imap/response_parser.rb', line 967

def capability_data
  data = []
  while true
    token = lookahead
    case token.symbol
    when T_CRLF, T_RBRA
      break
    when T_SPACE
      shift_token
      next
    end
    data.push(atom.upcase)
  end
  data
end

# File 'lib/net/imap/response_parser.rb', line 960

def capability_response
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  UntaggedResponse.new(name, capability_data, @str)
end

# File 'lib/net/imap/response_parser.rb', line 1259

def case_insensitive_string
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    return nil
  end
  token = match(T_QUOTED, T_LITERAL)
  return token.value.upcase
end

# File 'lib/net/imap/response_parser.rb', line 1306

def charset
  if token = accept(T_QUOTED)
    token.value
  else
    atom
  end
end

# File 'lib/net/imap/response_parser.rb', line 1135

def charset_list
  result = []
  if accept(T_SPACE)
    match(T_LPAR)
    result << charset
    while accept(T_SPACE)
      result << charset
    end
    match(T_RPAR)
  end
  result
end

# File 'lib/net/imap/response_parser.rb', line 1291

def combine_adjacent(*tokens)
  result = "".b
  while token = accept(*tokens)
    result << token.value
  end
  if result.empty?
    parse_error('unexpected token %s (expected %s)',
                lookahead.symbol, args.join(" or "))
  end
  result
end

# File 'lib/net/imap/response_parser.rb', line 108

def continue_req
  match(T_PLUS)
  token = lookahead
  if token.symbol == T_SPACE
    shift_token
    return ContinuationRequest.new(resp_text, @str)
  else
    return ContinuationRequest.new(ResponseText.new(nil, ""), @str)
  end
end

# File 'lib/net/imap/response_parser.rb', line 238

def envelope
  @lex_state = EXPR_DATA
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    result = nil
  else
    match(T_LPAR)
    date = nstring
    match(T_SPACE)
    subject = nstring
    match(T_SPACE)
    from = address_list
    match(T_SPACE)
    sender = address_list
    match(T_SPACE)
    reply_to = address_list
    match(T_SPACE)
    to = address_list
    match(T_SPACE)
    cc = address_list
    match(T_SPACE)
    bcc = address_list
    match(T_SPACE)
    in_reply_to = nstring
    match(T_SPACE)
    message_id = nstring
    match(T_RPAR)
    result = Envelope.new(date, subject, from, sender, reply_to,
                          to, cc, bcc, in_reply_to, message_id)
  end
  @lex_state = EXPR_BEG
  return result
end

# File 'lib/net/imap/response_parser.rb', line 231

def envelope_data
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return name, envelope
end

# File 'lib/net/imap/response_parser.rb', line 1209

def flag_list
  if @str.index(/\(([^)]*)\)/ni, @pos)
    @pos = $~.end(0)
    return $1.scan(FLAG_REGEXP).collect { |flag, atom|
      if atom
        atom
      else
        flag.capitalize.intern
      end
    }
  else
    parse_error("invalid flag list")
  end
end

# File 'lib/net/imap/response_parser.rb', line 273

def flags_data
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return name, flag_list
end

# File 'lib/net/imap/response_parser.rb', line 736

def flags_response
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return UntaggedResponse.new(name, flag_list, @str)
end

# File 'lib/net/imap/response_parser.rb', line 689

def format_string(str)
  case str
  when ""
    return '""'
  when /[\x80-\xff\r\n]/n
    # literal
    return "{" + str.bytesize.to_s + "}" + CRLF + str
  when /[(){ \x00-\x1f\x7f%*"\\]/n
    # quoted string
    return '"' + str.gsub(/["\\]/n, "\\\\\\&") + '"'
  else
    # atom
    return str
  end
end

# File 'lib/net/imap/response_parser.rb', line 814

def getacl_response
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  mailbox = astring
  data = []
  token = lookahead
  if token.symbol == T_SPACE
    shift_token
    while true
      token = lookahead
      case token.symbol
      when T_CRLF
        break
      when T_SPACE
        shift_token
      end
      user = astring
      match(T_SPACE)
      rights = astring
      data.push(MailboxACLItem.new(user, rights, mailbox))
    end
  end
  return UntaggedResponse.new(name, data, @str)
end

# File 'lib/net/imap/response_parser.rb', line 764

def getquota_response
  # If quota never established, get back
  # `NO Quota root does not exist'.
  # If quota removed, get `()' after the
  # folder spec with no mention of `STORAGE'.
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  mailbox = astring
  match(T_SPACE)
  match(T_LPAR)
  token = lookahead
  case token.symbol
  when T_RPAR
    shift_token
    data = MailboxQuota.new(mailbox, nil, nil)
    return UntaggedResponse.new(name, data, @str)
  when T_ATOM
    shift_token
    match(T_SPACE)
    token = match(T_NUMBER)
    usage = token.value
    match(T_SPACE)
    token = match(T_NUMBER)
    quota = token.value
    match(T_RPAR)
    data = MailboxQuota.new(mailbox, usage, quota)
    return UntaggedResponse.new(name, data, @str)
  else
    parse_error("unexpected token %s", token.symbol)
  end
end

# File 'lib/net/imap/response_parser.rb', line 797

def getquotaroot_response
  # Similar to getquota, but only admin can use getquota.
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  mailbox = astring
  quotaroots = []
  while true
    token = lookahead
    break unless token.symbol == T_SPACE
    shift_token
    quotaroots.push(astring)
  end
  data = MailboxQuotaRoot.new(mailbox, quotaroots)
  return UntaggedResponse.new(name, data, @str)
end

# File 'lib/net/imap/response_parser.rb', line 983

def id_response
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  token = match(T_LPAR, T_NIL)
  if token.symbol == T_NIL
    return UntaggedResponse.new(name, nil, @str)
  else
    data = {}
    while true
      token = lookahead
      case token.symbol
      when T_RPAR
        shift_token
        break
      when T_SPACE
        shift_token
        next
      else
        key = string
        match(T_SPACE)
        val = nstring
        data[key] = val
      end
    end
    return UntaggedResponse.new(name, data, @str)
  end
end

# File 'lib/net/imap/response_parser.rb', line 722

def ignored_response
  while lookahead.symbol != T_CRLF
    shift_token
  end
  return IgnoredResponse.new(@str)
end

# File 'lib/net/imap/response_parser.rb', line 280

def internaldate_data
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  token = match(T_QUOTED)
  return name, token.value
end

# File 'lib/net/imap/response_parser.rb', line 743

def list_response
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return UntaggedResponse.new(name, mailbox_list, @str)
end

# File 'lib/net/imap/response_parser.rb', line 1383

def lookahead
  @token ||= next_token
end

# File 'lib/net/imap/response_parser.rb', line 750

def mailbox_list
  attr = flag_list
  match(T_SPACE)
  token = match(T_QUOTED, T_NIL)
  if token.symbol == T_NIL
    delim = nil
  else
    delim = token.value
  end
  match(T_SPACE)
  name = astring
  return MailboxList.new(attr, delim, name)
end

# File 'lib/net/imap/response_parser.rb', line 1351

def match(*args, lex_state: @lex_state)
  if @token && lex_state != @lex_state
    parse_error("invalid lex_state change to %s with unconsumed token",
                lex_state)
  end
  begin
    @lex_state, original_lex_state = lex_state, @lex_state
    token = lookahead
    unless args.include?(token.symbol)
      parse_error('unexpected token %s (expected %s)',
                  token.symbol.id2name,
                  args.collect {|i| i.id2name}.join(" or "))
    end
    shift_token
    return token
  ensure
    @lex_state = original_lex_state
  end
end

# File 'lib/net/imap/response_parser.rb', line 464

def media_type
  mtype = case_insensitive_string
  token = lookahead
  if token.symbol != T_SPACE
    return mtype, nil
  end
  match(T_SPACE)
  msubtype = case_insensitive_string
  return mtype, msubtype
end

# File 'lib/net/imap/response_parser.rb', line 712

def modseq_data
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  match(T_LPAR)
  modseq = number
  match(T_RPAR)
  return name, modseq
end

# File 'lib/net/imap/response_parser.rb', line 193

def msg_att(n)
  match(T_LPAR)
  attr = {}
  while true
    token = lookahead
    case token.symbol
    when T_RPAR
      shift_token
      break
    when T_SPACE
      shift_token
      next
    end
    case token.value
    when /\A(?:ENVELOPE)\z/ni
      name, val = envelope_data
    when /\A(?:FLAGS)\z/ni
      name, val = flags_data
    when /\A(?:INTERNALDATE)\z/ni
      name, val = internaldate_data
    when /\A(?:RFC822(?:\.HEADER|\.TEXT)?)\z/ni
      name, val = rfc822_text
    when /\A(?:RFC822\.SIZE)\z/ni
      name, val = rfc822_size
    when /\A(?:BODY(?:STRUCTURE)?)\z/ni
      name, val = body_data
    when /\A(?:UID)\z/ni
      name, val = uid_data
    when /\A(?:MODSEQ)\z/ni
      name, val = modseq_data
    else
      parse_error("unknown attribute `%s' for {%d}", token.value, n)
    end
    attr[name] = val
  end
  return attr
end

# File 'lib/net/imap/response_parser.rb', line 1046

def namespace
  match(T_LPAR)
  prefix = match(T_QUOTED, T_LITERAL).value
  match(T_SPACE)
  delimiter = string
  extensions = namespace_response_extensions
  match(T_RPAR)
  Namespace.new(prefix, delimiter, extensions)
end

# File 'lib/net/imap/response_parser.rb', line 1012

def namespace_response
  @lex_state = EXPR_DATA
  token = lookahead
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  personal = namespaces
  match(T_SPACE)
  other = namespaces
  match(T_SPACE)
  shared = namespaces
  @lex_state = EXPR_BEG
  data = Namespaces.new(personal, other, shared)
  return UntaggedResponse.new(name, data, @str)
end

# File 'lib/net/imap/response_parser.rb', line 1056

def namespace_response_extensions
  data = {}
  token = lookahead
  if token.symbol == T_SPACE
    shift_token
    name = match(T_QUOTED, T_LITERAL).value
    data[name] ||= []
    match(T_SPACE)
    match(T_LPAR)
    loop do
      data[name].push match(T_QUOTED, T_LITERAL).value
      break unless lookahead.symbol == T_SPACE
      shift_token
    end
    match(T_RPAR)
  end
  data
end

# File 'lib/net/imap/response_parser.rb', line 1028

def namespaces
  token = lookahead
  # empty () is not allowed, so nil is functionally identical to empty.
  data = []
  if token.symbol == T_NIL
    shift_token
  else
    match(T_LPAR)
    loop do
      data << namespace
      break unless lookahead.symbol == T_SPACE
      shift_token
    end
    match(T_RPAR)
  end
  data
end

# File 'lib/net/imap/response_parser.rb', line 1391

def next_token
  case @lex_state
  when EXPR_BEG
    if @str.index(BEG_REGEXP, @pos)
      @pos = $~.end(0)
      if $1
        return Token.new(T_SPACE, $+)
      elsif $2
        return Token.new(T_NIL, $+)
      elsif $3
        return Token.new(T_NUMBER, $+)
      elsif $4
        return Token.new(T_ATOM, $+)
      elsif $5
        return Token.new(T_QUOTED,
                         $+.gsub(/\\(["\\])/n, "\\1"))
      elsif $6
        return Token.new(T_LPAR, $+)
      elsif $7
        return Token.new(T_RPAR, $+)
      elsif $8
        return Token.new(T_BSLASH, $+)
      elsif $9
        return Token.new(T_STAR, $+)
      elsif $10
        return Token.new(T_LBRA, $+)
      elsif $11
        return Token.new(T_RBRA, $+)
      elsif $12
        len = $+.to_i
        val = @str[@pos, len]
        @pos += len
        return Token.new(T_LITERAL, val)
      elsif $13
        return Token.new(T_PLUS, $+)
      elsif $14
        return Token.new(T_PERCENT, $+)
      elsif $15
        return Token.new(T_CRLF, $+)
      elsif $16
        return Token.new(T_EOF, $+)
      else
        parse_error("[Net::IMAP BUG] BEG_REGEXP is invalid")
      end
    else
      @str.index(/\S*/n, @pos)
      parse_error("unknown token - %s", $&.dump)
    end
  when EXPR_DATA
    if @str.index(DATA_REGEXP, @pos)
      @pos = $~.end(0)
      if $1
        return Token.new(T_SPACE, $+)
      elsif $2
        return Token.new(T_NIL, $+)
      elsif $3
        return Token.new(T_NUMBER, $+)
      elsif $4
        return Token.new(T_QUOTED,
                         $+.gsub(/\\(["\\])/n, "\\1"))
      elsif $5
        len = $+.to_i
        val = @str[@pos, len]
        @pos += len
        return Token.new(T_LITERAL, val)
      elsif $6
        return Token.new(T_LPAR, $+)
      elsif $7
        return Token.new(T_RPAR, $+)
      else
        parse_error("[Net::IMAP BUG] DATA_REGEXP is invalid")
      end
    else
      @str.index(/\S*/n, @pos)
      parse_error("unknown token - %s", $&.dump)
    end
  when EXPR_TEXT
    if @str.index(TEXT_REGEXP, @pos)
      @pos = $~.end(0)
      if $1
        return Token.new(T_TEXT, $+)
      else
        parse_error("[Net::IMAP BUG] TEXT_REGEXP is invalid")
      end
    else
      @str.index(/\S*/n, @pos)
      parse_error("unknown token - %s", $&.dump)
    end
  when EXPR_RTEXT
    if @str.index(RTEXT_REGEXP, @pos)
      @pos = $~.end(0)
      if $1
        return Token.new(T_LBRA, $+)
      elsif $2
        return Token.new(T_TEXT, $+)
      else
        parse_error("[Net::IMAP BUG] RTEXT_REGEXP is invalid")
      end
    else
      @str.index(/\S*/n, @pos)
      parse_error("unknown token - %s", $&.dump)
    end
  when EXPR_CTEXT
    if @str.index(CTEXT_REGEXP, @pos)
      @pos = $~.end(0)
      if $1
        return Token.new(T_TEXT, $+)
      else
        parse_error("[Net::IMAP BUG] CTEXT_REGEXP is invalid")
      end
    else
      @str.index(/\S*/n, @pos) #/
      parse_error("unknown token - %s", $&.dump)
    end
  else
    parse_error("invalid @lex_state - %s", @lex_state.inspect)
  end
end

# File 'lib/net/imap/response_parser.rb', line 1324

def nil_atom
  match(T_NIL)
  return nil
end

# File 'lib/net/imap/response_parser.rb', line 1224

def nstring
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    return nil
  else
    return string
  end
end

# File 'lib/net/imap/response_parser.rb', line 1314

def number
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    return nil
  end
  token = match(T_NUMBER)
  return token.value.to_i
end

# File 'lib/net/imap/response_parser.rb', line 177

def numeric_response
  n = number
  match(T_SPACE)
  token = match(T_ATOM)
  name = token.value.upcase
  case name
  when "EXISTS", "RECENT", "EXPUNGE"
    return UntaggedResponse.new(name, n, @str)
  when "FETCH"
    shift_token
    match(T_SPACE)
    data = FetchData.new(n, msg_att(n))
    return UntaggedResponse.new(name, data, @str)
  end
end

# File 'lib/net/imap/response_parser.rb', line 16

def parse(str)
  @str = str
  @pos = 0
  @lex_state = EXPR_BEG
  @token = nil
  return response
end

# File 'lib/net/imap/response_parser.rb', line 1510

def parse_error(fmt, *args)
  if IMAP.debug
    $stderr.printf("@str: %s\n", @str.dump)
    $stderr.printf("@pos: %d\n", @pos)
    $stderr.printf("@lex_state: %s\n", @lex_state)
    if @token
      $stderr.printf("@token.symbol: %s\n", @token.symbol)
      $stderr.printf("@token.value: %s\n", @token.value.inspect)
    end
  end
  raise ResponseParseError, format(fmt, *args)
end

# File 'lib/net/imap/response_parser.rb', line 1082

def resp_text
  token = match(T_LBRA, T_TEXT, lex_state: EXPR_RTEXT)
  case token.symbol
  when T_LBRA
    code = resp_text_code
    match(T_RBRA)
    accept_space # violating RFC
    ResponseText.new(code, text)
  when T_TEXT
    ResponseText.new(nil, token.value)
  end
end

# File 'lib/net/imap/response_parser.rb', line 1106

def resp_text_code
  token = match(T_ATOM)
  name = token.value.upcase
  case name
  when /\A(?:ALERT|PARSE|READ-ONLY|READ-WRITE|TRYCREATE|NOMODSEQ)\z/n
    result = ResponseCode.new(name, nil)
  when /\A(?:BADCHARSET)\z/n
    result = ResponseCode.new(name, charset_list)
  when /\A(?:CAPABILITY)\z/ni
    result = ResponseCode.new(name, capability_data)
  when /\A(?:PERMANENTFLAGS)\z/n
    match(T_SPACE)
    result = ResponseCode.new(name, flag_list)
  when /\A(?:UIDVALIDITY|UIDNEXT|UNSEEN)\z/n
    match(T_SPACE)
    result = ResponseCode.new(name, number)
  else
    token = lookahead
    if token.symbol == T_SPACE
      shift_token
      token = match(T_TEXT, lex_state: EXPR_CTEXT)
      result = ResponseCode.new(name, token.value)
    else
      result = ResponseCode.new(name, nil)
    end
  end
  return result
end

# File 'lib/net/imap/response_parser.rb', line 89

def response
  token = lookahead
  case token.symbol
  when T_PLUS
    result = continue_req
  when T_STAR
    result = response_untagged
  else
    result = response_tagged
  end
  while lookahead.symbol == T_SPACE
    # Ignore trailing space for Microsoft Exchange Server
    shift_token
  end
  match(T_CRLF)
  match(T_EOF)
  return result
end

# File 'lib/net/imap/response_parser.rb', line 170

def response_cond
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return UntaggedResponse.new(name, resp_text, @str)
end

# File 'lib/net/imap/response_parser.rb', line 161

def response_tagged
  tag = astring_chars
  match(T_SPACE)
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return TaggedResponse.new(tag, name, resp_text, @str)
end

# File 'lib/net/imap/response_parser.rb', line 119

def response_untagged
  match(T_STAR)
  match(T_SPACE)
  token = lookahead
  if token.symbol == T_NUMBER
    return numeric_response
  elsif token.symbol == T_ATOM
    case token.value
    when /\A(?:OK|NO|BAD|BYE|PREAUTH)\z/ni
      return response_cond
    when /\A(?:FLAGS)\z/ni
      return flags_response
    when /\A(?:ID)\z/ni
      return id_response
    when /\A(?:LIST|LSUB|XLIST)\z/ni
      return list_response
    when /\A(?:NAMESPACE)\z/ni
      return namespace_response
    when /\A(?:QUOTA)\z/ni
      return getquota_response
    when /\A(?:QUOTAROOT)\z/ni
      return getquotaroot_response
    when /\A(?:ACL)\z/ni
      return getacl_response
    when /\A(?:SEARCH|SORT)\z/ni
      return search_response
    when /\A(?:THREAD)\z/ni
      return thread_response
    when /\A(?:STATUS)\z/ni
      return status_response
    when /\A(?:CAPABILITY)\z/ni
      return capability_response
    when /\A(?:NOOP)\z/ni
      return ignored_response
    else
      return text_response
    end
  else
    parse_error("unexpected token %s", token.symbol)
  end
end

# File 'lib/net/imap/response_parser.rb', line 300

def rfc822_size
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return name, number
end

# File 'lib/net/imap/response_parser.rb', line 288

def rfc822_text
  token = match(T_ATOM)
  name = token.value.upcase
  token = lookahead
  if token.symbol == T_LBRA
    shift_token
    match(T_RBRA)
  end
  match(T_SPACE)
  return name, nstring
end

# File 'lib/net/imap/response_parser.rb', line 840

def search_response
  token = match(T_ATOM)
  name = token.value.upcase
  token = lookahead
  if token.symbol == T_SPACE
    shift_token
    data = []
    while true
      token = lookahead
      case token.symbol
      when T_CRLF
        break
      when T_SPACE
        shift_token
      when T_NUMBER
        data.push(number)
      when T_LPAR
        # TODO: include the MODSEQ value in a response
        shift_token
        match(T_ATOM)
        match(T_SPACE)
        match(T_NUMBER)
        match(T_RPAR)
      end
    end
  else
    data = []
  end
  return UntaggedResponse.new(name, data, @str)
end

# File 'lib/net/imap/response_parser.rb', line 654

def section
  str = String.new
  token = match(T_LBRA)
  str.concat(token.value)
  token = match(T_ATOM, T_NUMBER, T_RBRA)
  if token.symbol == T_RBRA
    str.concat(token.value)
    return str
  end
  str.concat(token.value)
  token = lookahead
  if token.symbol == T_SPACE
    shift_token
    str.concat(token.value)
    token = match(T_LPAR)
    str.concat(token.value)
    while true
      token = lookahead
      case token.symbol
      when T_RPAR
        str.concat(token.value)
        shift_token
        break
      when T_SPACE
        shift_token
        str.concat(token.value)
      end
      str.concat(format_string(astring))
    end
  end
  token = match(T_RBRA)
  str.concat(token.value)
  return str
end

# File 'lib/net/imap/response_parser.rb', line 1387

def shift_token
  @token = nil
end

# File 'lib/net/imap/response_parser.rb', line 933

def status_response
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  mailbox = astring
  match(T_SPACE)
  match(T_LPAR)
  attr = {}
  while true
    token = lookahead
    case token.symbol
    when T_RPAR
      shift_token
      break
    when T_SPACE
      shift_token
    end
    token = match(T_ATOM)
    key = token.value.upcase
    match(T_SPACE)
    val = number
    attr[key] = val
  end
  data = StatusData.new(mailbox, attr)
  return UntaggedResponse.new(name, data, @str)
end

# File 'lib/net/imap/response_parser.rb', line 1243

def string
  token = lookahead
  if token.symbol == T_NIL
    shift_token
    return nil
  end
  token = match(T_QUOTED, T_LITERAL)
  return token.value
end

# File 'lib/net/imap/response_parser.rb', line 1255

def string_token?(token)
  return STRING_TOKENS.include?(token.symbol)
end

# File 'lib/net/imap/response_parser.rb', line 1077

def text
  match(T_TEXT, lex_state: EXPR_TEXT).value
end

# File 'lib/net/imap/response_parser.rb', line 729

def text_response
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return UntaggedResponse.new(name, text)
end

# File 'lib/net/imap/response_parser.rb', line 898

def thread_branch(token)
  rootmember = nil
  lastmember = nil

  while true
    shift_token    # ignore first T_LPAR
    token = lookahead

    case token.symbol
    when T_NUMBER
      # new member
      newmember = ThreadMember.new(number, [])
      if rootmember.nil?
        rootmember = newmember
      else
        lastmember.children << newmember
      end
      lastmember = newmember
    when T_SPACE
      # do nothing
    when T_LPAR
      if rootmember.nil?
        # dummy member
        lastmember = rootmember = ThreadMember.new(nil, [])
      end

      lastmember.children << thread_branch(token)
    when T_RPAR
      break
    end
  end

  return rootmember
end

# File 'lib/net/imap/response_parser.rb', line 871

def thread_response
  token = match(T_ATOM)
  name = token.value.upcase
  token = lookahead

  if token.symbol == T_SPACE
    threads = []

    while true
      shift_token
      token = lookahead

      case token.symbol
      when T_LPAR
        threads << thread_branch(token)
      when T_CRLF
        break
      end
    end
  else
    # no member
    threads = []
  end

  return UntaggedResponse.new(name, threads, @str)
end

# File 'lib/net/imap/response_parser.rb', line 705

def uid_data
  token = match(T_ATOM)
  name = token.value.upcase
  match(T_SPACE)
  return name, number
end